Remove extern keyword from function declarations

Function declarations implicitly have external linkage so do not
need the extern keyword.

Change-Id: Ia0549786796d8bf5956487e8996450a0b3d79f32
diff --git a/services/spd/tspd/tspd_private.h b/services/spd/tspd/tspd_private.h
index fbb0388..fb71922 100644
--- a/services/spd/tspd/tspd_private.h
+++ b/services/spd/tspd/tspd_private.h
@@ -188,11 +188,11 @@
 /*******************************************************************************
  * Function & Data prototypes
  ******************************************************************************/
-extern uint64_t tspd_enter_sp(uint64_t *c_rt_ctx);
-extern void __dead2 tspd_exit_sp(uint64_t c_rt_ctx, uint64_t ret);
-extern uint64_t tspd_synchronous_sp_entry(tsp_context_t *tsp_ctx);
-extern void __dead2 tspd_synchronous_sp_exit(tsp_context_t *tsp_ctx, uint64_t ret);
-extern int32_t tspd_init_secure_context(uint64_t entrypoint,
+uint64_t tspd_enter_sp(uint64_t *c_rt_ctx);
+void __dead2 tspd_exit_sp(uint64_t c_rt_ctx, uint64_t ret);
+uint64_t tspd_synchronous_sp_entry(tsp_context_t *tsp_ctx);
+void __dead2 tspd_synchronous_sp_exit(tsp_context_t *tsp_ctx, uint64_t ret);
+int32_t tspd_init_secure_context(uint64_t entrypoint,
 					uint32_t rw,
 					uint64_t mpidr,
 					tsp_context_t *tsp_ctx);